The document discusses the evolution of computer architecture since 1950, including major advances such as the family concept, microprogrammed control units, cache memory, and pipelining. It specifically focuses on the Reduced Instruction Set Computer (RISC) architecture, which follows four design rules: instructions are simple, pipelines are deep, many registers are used, and memory access only occurs through load and store instructions.

1. UNIT I:
RISC AND CISC ARCHITECTURE

2. INTRODUCTION
Since 1950 there have been remarkably innovations happened in the
areas of computer organization and architecture.
The following are some of the major advances since the birth of the
computer:
 The family concept: Different Implementations for the Same Architecture
 Microprogrammed control unit: eases the task of designing and implementing the control
unit
 Cache memory: Enhanced Performance memory
 Pipelining: Fetching next instructions well in advance for execution
 Multiple processors: Parallelism
 Reduced instruction set computer (RISC) architecture:

3. REDUCED INSTRUCTION SET
COMPUTER (RISC)
ARCHITECTURE:

4. RISC DESIGN PHILOSOPHY
The RISC philosophy is implemented with four major design rules:
1. Instructions
2. Pipelines
3. Registers
4. Load-store architecture